A SDN is a new network architecture in which control and management are separated. In the SDN, a dedicated device deploys a high-level policy, and a network device forwards data under the guidance of the high-level policy such that many complex functions carried by the network device are reduced, and flexibility and an entirety of a network can be improved.
An OPENFLOW technology, as a southbound interface of an SDN architecture, is a key representative technology in the SDN field. In an OPENFLOW network, a topology and information of an entire network are managed using an OPENFLOW controller. In a large-scale data center architecture or a cross-operator OPENFLOW network architecture, the OPENFLOW network is divided into different areas, and a controller is configured for each area. When receiving a data transmission request, a controller calculates a network path according to networking information stored in the controller, and sends a path out of a local domain to each corresponding controller. After receiving path information, the corresponding controller directly sends the path information to a switching node in a domain of the corresponding controller.
Each controller in the foregoing network architecture can acquire the networking information, and when a controller is attacked, the networking information is leaked.